BY H. GKEKi SMITH. 591 



and, if so, ail the interbovine cycle may be assumed to have been 

 observed. The diplococcus bodies, the amoeba, the mature 

 apiosoma with its capsule complete one portion of the life history. 

 Since the multiplication of the parasite is so rapid it almost 

 follows that all stages of the interbovine life cycle must have 

 been observed by those who investigated the blood. The inter- 

 pretation alone is wanting, and this is supplied if, for vacuole, we 

 read capsule. Celli and San tori's observations upon fresh specimens 

 bear out this interpretation. They noted that the mature 

 apiosoma had a granule at the swollen end. This appearance 

 would be caused by the refraction of the capsule. They make no 

 mention of a vacuole, nor do they figure one in their drawings. 

 The granule which they represent by a tiny circle occupies a 

 position which coincides with the centre of the capsule. They 

 mention that they saw the pear-shape alter, after a long time, to 

 an egg or I'ound shape. Such a change would be brought about 

 by the enlargement of the capsule and the shrinkage and degra- 

 dation of the body of the apiosoma concomitant with the 

 maturation and persistence of the capsule. Another observation 

 showed that the apiosoma, without altering its shape, suddenly 

 disappeared from the corpuscle. This would happen were the 

 capsule to rupture and liberate its contents simultaneously with 

 the collapse of the other portions. 



With regard to the susceptibility of other animals, Theobald 

 Smith found that rabbits, guinea-pigs, goats and sheep showed 

 neither a multiplication of the parasite nor symptoms of the 

 disease when inoculated with virulent blood. Similarly, Celli and 

 Santori injected virulent blood into rabbits, guinea-pigs, mice, 

 rats, cats and dogs, but without result. They mention, however, 

 that death sometimes ensued, but the parasite could not be found. 

 The pseudo-parasitic forms were present. These authors ma}' lie 

 wrong in considering all the small diplococcus bodies as being 

 pseudo-parasitic. Although the {Darasitic forms were not found, 

 the injected blood maintained its virulence through a series of three 

 guinea-pigs. Nicolle and Adil Bey found that 1 c.c. of virulent 

 blood caused the death of guinea-pigs. Sidney Hunt and Collins 



